Hemstitch sewing-machine.



No. 650,482. Patented May 29, I900.

B. ROSCHACH.

HEMSTITCH SEWING MACHINE.

1 (Application filed Dec. 21, 18 96.) (No Model. 2 Sheets-Sheet I.

(No Mudel.)

B. ROSCHACH.

HEMSTITCH SEWING MACHINE.

(Apglication filed Dec. 21, 1896.)

Patented May 29, won;

2 Sheets$heet 2.

UNITED STATES PATENT G FIQE.

BENEDIKT ROSOHAOH, on ST. GALL, SWITZERLAND, ASSIGNOR TO EMANUEL MEYER, 0E HEEIsAU, SWITZERLAND.

SPECIFICATION forming part of Letters Patent No. 650,482, dated May 29, 1900. I

Application filed December 21, 1896. Serial No. 616,456. (No model.)

To all whom it may concern.- I

Be it known that I, BENEDIKT ROSOHAOH, a citizen of the Republic of Switzerland, and a resident of St. Gall, in the Republic of Switzerland, have invented certain new and useful Improvements in Hemstitch Sewing-Machines, (for which I have obtained a patent in Switzerland, No. 11,7 43, dated March 2, 1896,) of which the following is a specification.

This invention relates to certain improvemonts in hemstitch sewing-machines in which the formation of the hem is formed by a fixed piercer and only two movable needles, which are arranged on both sides of and in a row with the piercer, and in such a manner that they can be moved by means of suitable devices to positions either converging toward the piercer or parallel with the same. The hernstitch sewing-machines heretofore in use always required, besides the 'fizied piercer, more than two needles, the adjustment of which, owing to their greater number, required a relatively more complicated actuating and adjusting mechanism. In the sewing-m achine which forms the subject-matter of this application only two needles are used in connection with the piercer, which perform exactly the same work as the larger number of needles heretofore used, so that a considerable simplification of the actuating mechanisms, and thereby a more reliable functioning and an increased output as compared to the machines heretofore in use, is obtained.

In the accompanying drawings, Figure 1 represents a side elevation of my improved hemstitch sewing-machine, showing one construction of the same. Fig. 2 is an end eleva tion. Fig. 3 is a detail of the disk for tripping the latch. Figs. 4: and 5 are'side elevations of the needles, shown in their two operat-.

reference.

The machine represented in the drawings is built upon the general principle of an ordinary sowing rnachine, with longitudinal shuttle-races in which the shuttles are both moved forward in the same direction. The machine is operated as a hemstitch sewingmachine in the well-known manner between two successive fabric feeds that is to say, in every working phase of the machine are produced three stitches, two of which are formed by the piercer and the cooperating converging needles, which form the inner hemstitch, respectively, before and after the feed, and one stitch in which the needles are parallel with the piercer, so as to produce lateral stitches, which latterareso timed that they are produced after each feed between the two stitches made by the converging needles. The formation of the stitches between the needlethreads and shuttle-threads corresponds to that used for hemstitc'hes namely, that during the upward motion of the needles the needle -threads are drawn out into loops, through which the shuttles are passed. By arranging a recess in the partition between the shuttle-races the loop of one needle is caused to face one shuttle, while the loop of the other needle is placed in the path of the other shuttle, so that through each loop at opposite sides of the partition the corresponding shuttle is passed.

The needle-barA carries at its lower end a T-shaped head a, into which the piercer b is centrally inserted, while the two needles a a are attached to levers a of, which are pivoted at a to the cross-head a of the piercer b equidistantly from the latter, so as to be movable relatively thereto. To the needle-bar A are attached above the cross head a; fiat springs f, the free ends of which press on the levers a a, so that the needles are forced with their points against the piercer, so as to form contact with the same and be normally retained in this position, as shown in Fig. 5. The piercer b is provided with a spear-like point which is provided atboth sides with recesses in which the needle-points enter. The

needles assume this converging position, as before referred to, while making two stitches for every Working phase of the machinenamely, duringthe piercing before and after the feed, whereby the inner stitch is'formed. The needles are moved into open position inlateraldirection.

that is to say, parallel with the piercer when forming the side stitches by means of a rod 0, which is moved in downward direction at the proper time, so as to press with its conically-formed head 0 between pins a a lo-' piercer, as shown in Fig. 4. The rod 0 is re.

tained in upward position during the pressing of the closed needles by means of a latch d, which is applied 'to a transverse pivotcl 7' on the arm of the machine, while its upper endengages a collar 0 on the rod 0, so as to hold the latter against the tension of a helical spring f in its uppermost position, so that the needle-levers are not acted upon by the head a, but are placed by the pressure of the springs ff in converging position relatively to the piercer and in contact with the point of the same. When the piercing of the fabric is to be made with the needles in position parallel to the piercer, the latch cl is automatically moved so as to clear the collar 0 of the rod 0, while by the pressure of the spring f the rod is moved downward into the position shown in Fig. 4:, so that the head 0 is placed between the pins a a, and the rod 0 follows the downward motion of the needle-barA and holds the needles in their parallel position during the piercing of the fabric. With each upward motion of the. needle-barA the rod 0 is raised by the contact of thepins a a with the lateral projections c c of the head 0, so that at the proper time when the lateral motion of the latch takes place the collar 0 is located above the same and the latch is free to be moved inwardly This motion is imparted to the latch d bya torsion-spring f one end of which acts on a pin d on the latch, while the other end presses on the arm of the machine. This motion of the latch is imparted by a disk 8, that is operated from the main shaft to of the machine, said disk being provided with a lateral pin 8', which engages at the proper time a finger d on the latch d,

whereby the latter is turned on its axis, and' thereby the latch moved and held in its position, so that the rod 0 can be moved in downward direction with the needle-bar A. Assoon as the pin 8 has passed the finger d the rod 0 moves with the needle-bar A in upward-direction and the collar 0 pushes the latch 61 in lateral direction, so that the latter before the reversing of the motion of the needle-bar A and rod 0 is placed below the collar c and for the next two stitches the rod 0 is retained in its raised position, while the needles assume their convergingposition relatively to the piercer.

Any suitable shuttle mechanism 'may be used in connection with my invention-as, for instance, that shown in Fig. 1, in which both shuttles receive a simultaneous rectilinear motion in the same forward direction from a vertical shaft 20, which is driven from the main shaft to by bevel-wheels 9" r, a crank 70, and a connecting-rod it, applied to the cross-piece connecting the shuttle-carriers, so as to produce a simultaneous motion of the carriers, and accordingly of the shuttles, in the well-known manner.

It may be mentioned that this sewing-machine can also be used as an ordinary twothread sewing-machine, for which purpose holes s 3 are arranged in the disk 8 for the insertion of pins, which will then form, with thepins, an equilateral triangle on the disk 3 in such a manner that for each stitch the latch dis moved out of the collar d of the rod 0, and the latter remains continuously in the position as shown in Fig. 4' and follows the up-and-down motion of the needle-bar for each stitch, so that the machine can be operated continuouslywith parallel needles. When the machine is used as a two-thread sewing-machine, the piercer b has to be removed from its socket, as it is notnecessary, and during the operation would only-interfere with the regular formation'of the stitches.

Having thus described my invention, I claim as new and desire to secure by Letters Patent- 1. In ahemstitch sewing-machine, the combination of a piercer, laterally-oscillating needles, needle-levers carrying said needles, a rod movable toward and from said needle-levers and having a head for operating the latter, a latch for intermittently engaging said rod, and meansfor moving said latch into and out of engaging position with said rod whereby said rod moves said levers and releases them intermittently.

2. In ahemstitch sewing-machine, the combination of a piercer, laterally-oscillating needles, pivotedneedle-levers carrying such needles, and normally holding them in a position converging with said piercer, and a movable part adapt-ed to engage such needle-levers to intermittently wedge them in their outward positions.

3. In a hemstitch sewing-machine,-the combination of a piercer and a pair of pivoted and spring-actuated needle-levers provided with needles arranged one at each side of the piercer, with a vertically-movable rod having a head adaptedto actuate the needle levers and overcome the action of their springs, sub stantially as set forth.

4. In a hemstitch sewing-machine, the combination with a piercer, and laterally-oscillating needles, of a spring actuated rod guided parallel with the needle-bar and provided with a collar, a pivoted spring-actuated latch located below the collar, and means for moving the latch out of the path of thecollar so that the latch either engages the collar and holds the rod in raised position or releases the collar and produces the engagement of the head of the spring-actuated rod with the me dle-levers so that their needles are pressed I out of the path of the collar so that the paragainst the point of the piercer, substantially as set forth.

5. In a hemstitch sewing-machine, the combination with a needle-bar having a fixed piercer and laterally movable needles; a spring-actuated rod, guided parallel with the needle-bar; a pivoted and spring-actuated latch adapted to engage a collar on said rod, and means, operated by the main shaft of the machine, for intermittently moving the latch allel position of the needles with the piercer can be changed to converging position toward the piercer, substantially as set forth.

I11 testimony whereof I hereunto sign my name, in the presence of two subscribing Witnesses, this 19th day of November, 1896.

BENEDIKT ROSOHACl-I.

WVitnesses:

Mom'rz VEITH, H. LABHORT. 

